The burden of tobacco use falls disproportionately on low-income populations, through high rates of primary smoking and exposure to secondhand smoke. The remarkable progress in creating smoke-free environments in the U.S. over the past two decades has left smokers'homes as a significant source of exposure to secondhand smoke for both children and nonsmoking adults. Intervention research that identifies effective and practical strategies for reaching the minority of households that still allow smoking in the home has considerable potential to reduce exposure to secondhand smoke, but suitable channels to reach low-income families are limited. The proposed research will develop, evaluate and disseminate a brief smoke-free homes intervention through the established national infrastructure of 2-1-1 call centers. 2-1-1 is a nationally designated 3-digit telephone exchange, similar to 9-1-1 for emergencies or 4-1-1 for directory assistance, that links callers to community-based health and social services. Most 2-1-1 callers are low income. The proposed research has four specific aims: 1) Conduct formative research on intervention messages and materials for promoting smoke-free homes in low-income populations, applicable to both smokers and nonsmokers as household change agents;2) Conduct a randomized controlled trial in the Atlanta 2-1-1 service area to evaluate the efficacy of a brief intervention to create smoke-free homes among 2-1-1 callers;3) Conduct replication studies in Houston and North Carolina 2-1-1 systems to systematically test the intervention in varied populations and tobacco control climates;and 4) Disseminate the research tested smoke-free homes intervention through a national grants program to 2-1-1 systems and through the Tobacco Technical Assistance Consortium's linkages to the state and local tobacco control infrastructure in the U.S.